import matplotlib.pyplot as plt import numpy as np def lorenz(xyz, *, s=10, r=28, b=2.667): """ Parameters ---------- xyz : array-like, shape (3,) Point of interest in three-dimensional space. s, r, b : float Parameters defining the Lorenz attractor. Returns ------- xyz_dot : array, shape (3,) Values of the Lorenz attractor's partial derivatives at *xyz*. """ x, y, z = xyz x_dot = s*(y - x) y_dot = r*x - y - x*z z_dot = x*y - b*z return np.array([x_dot, y_dot, z_dot]) dt = 0.01 num_steps = 10000 xyzs = np.empty((num_steps + 1, 3)) # Need one more for the initial values xyzs[0] = (0., 1., 1.05) # Set initial values # Step through "time", calculating the partial derivatives at the current point # and using them to estimate the next point for i in range(num_steps): xyzs[i + 1] = xyzs[i] + lorenz(xyzs[i]) * dt # Plot ax = plt.figure().add_subplot(projection='3d') ax.plot(*xyzs.T, lw=0.5) ax.set_xlabel("X Axis") ax.set_ylabel("Y Axis") ax.set_zlabel("Z Axis") ax.set_title("Lorenz Attractor") plt.show()